- 期刊
- OpenAccess
不同乾燥方法對龍鬚菜品質之影響
Effects of Different Drying Methods on Quality of Gracilar
摘要
本研究比較不同乾燥方法下龍鬚菜品質和保健成分的影響。五種乾燥方法分別為50℃、60℃和70℃的熱風乾燥、日曬乾燥及冷凍乾燥，除分析乾燥龍鬚菜的水分含量、水活性、復水率、色澤外，並測其保健成分中的鈣含量、多醣含量、葉綠素含量和捕捉DPPH自由基能力。結果顯示，各乾燥方法所得龍鬚菜的水活性在0.6左右，復水率以冷凍乾燥者最高為5.17，其他乾燥方法亦在4.50以上。冷凍乾燥的色澤最接近新鮮龍鬚菜，日曬乾燥者最暗。冷凍乾燥者的鈣和葉綠素和多醣含量皆較其他乾燥方法為高，而三種不同溫度熱風乾燥以50℃熱風乾燥者含較高的保健成分，而70℃熱風乾燥會明顯降低龍鬚菜的葉綠素和多醣含量。在捕捉DPPH自由基能力，冷凍乾燥者達16.87%，日曬乾燥最低只有6.50%。整體而言，冷凍乾燥龍鬚菜在復水率、色澤、鈣含量及捕捉DPPH自由基能力的品質最佳，三種不同的熱風乾燥溫度以50℃在捕捉DPPH自由基能力和葉綠素較佳，而高溫70℃對保健成分流失較嚴重。
並列摘要
The objective of this study was to compare the effects of different drying methods on the quality and functional components of gracilar. There were five drying methods such as 50℃, 60℃and 70℃hot-air drying and freeze-drying. The dried products were analyzed as water content, water activity, rehydration ratio, color and functional components such as calcium, polysaccharide, chlorophyll and DPPH radical scavenging activity. The results showed that the water activities of each dried products were about 0.6. The rehydration ration of freeze-dried product was 5.17 and it was much higher than the others. The color of freeze-dried product was similar the fresh one, but the color of sun dried product was the darkest. The freeze-dried product had higher calcium, chlorophyll and polysaccharide contents than the other dried products. The 50℃ hot-air dried product had higher functional components among three different temperature hot-air dried products. And the content of chlorophyll and polysaccharide in gracilar decreased significantly during hot-air drying at 70℃. The results showed that the freeze-dried product and 16.87% DPPH radical scavenging activity and the sun dried product only had 6.5%. Overall, the freeze-dried product had the best quality. The 70℃ hot-air dried product had a large loss of functional components such as antioxidant and chlorophyll than 50℃ hot-air dried product.